[BUG] Unable to upload large files when using OCIS backend

Actual behavior

When trying to upload a big file (or a small one with limited bandwidth), the upload always fails.
When looking at the reverse proxy logs on server side (traefik), there are some kind of timeout after ~60 seconds (most likely due to traefik's default read timeout of 60s).
Then, If I try to restart the upload, the upload starts again from the beginning.

When searching in existing issues, there is a 4 year old issue (#2978) referring to file upload but I don't know the current status of this feature.

Expected behavior

I was expecting :

• large files to be uploaded in multiple chunks
• failed uploads to restarts from where it ended

Steps to reproduce

1. Use ocis as backend (5.0.8), with traefik as reverse proxy
2. Try to upload a big file (which takes more than 60 seconds to upload)
3. wait 60 seconds

Environment data

ownCloud app version: 4.4.0
ownCloud server version: ocis 5.0.8 behind traefik

Logs

I can provide logs if needed, but I think the issue is easy enough to reproduce.

Start by tracing the Android app's upload flow when connected to an OCIS 5.0.8 backend behind Traefik, then reproduce an upload lasting more than 60 seconds. Compare the current retry behavior with the requested chunked and resumable upload behavior; done means large or bandwidth-limited uploads survive the proxy timeout and resume from their previous progress.